Which of the following market structures is most likely to experience a large inflow of new firms into the market?

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B Oligopoly market

The difficulty or ease with which new firms can enter the market for a product is also a characteristic of market structures. New firms can enter market structures classified as perfect competition or monopolistic competition relatively easily. In these cases, barriers to entry are considered low, as only a small investment may be required to enter the market. In oligopoly, barriers to entry is considered very high—huge amounts of investment, determined by the very nature of the product and the production process, are needed to enter these markets.

I do not for sure but I think it is- Oligopoly market